Application specified integrated circuit for use in wavefront detection

Abstract

A device for detecting a wavefront that is defined by a plurality of contiguous light beams includes an array of lenslets for isolating the individual light beams and focusing each individual light beam to a focal point in an x-y plane. The device also has a plurality of clusters which are positioned in the x-y plane, and each cluster includes a plurality of pixels that are arranged in rows aligned in an x-direction, and columns aligned in a y-direction. Additionally, each pixel of a cluster includes both a first photocell for generating an x-signal and a second photocell for generating a y-signal, respectively, in response to an illumination of the pixel by a light beam. Further, the device includes circuitry for converting the x and y signals to digital signals and then using the digital signals to determine an x-y position for the focal point of the particular light beam that is incident on the cluster. A computer then compares the respective x-y positions of the various focal points to detect the wavefront. Depending on the particular application of the device, either photodiodes or phototransistors may be selected for use as the photocells in the pixels.

What is claimed is:  
     
       1. A device for detecting a wavefront defined by a plurality of contiguous light beams which comprises: 
       an optical means for isolating each individual said light beam of said plurality of light beams;  
       an optical means for focusing each individual said light beam to a focal point in an x-y plane;  
       a plurality of clusters, each said cluster including a plurality of rows and a plurality of columns with each row having a plurality of pixels aligned in an x-direction and each column having a plurality of pixels aligned in a y-direction, and wherein each said pixel includes a first photodetector for generating a first electrical current in response to an illumination thereof by said focal pint and a second photodetector for generating a second electrical current in response to an illumination thereof by said focal point;  
       a plurality of first electronic circuits for summing said first electrical currents generated by said first photodetectors in each row to generate a respective y-signal for said row;  
       a plurality of second electronic circuits for summing said second electrical currents generated by said second photodetectors in each column to generate a respective x-signal for said column;  
       an electronic means for receiving said x-signals and said y-signals from said cluster to determine an x-y position for said focal point of said individual light beam incident on said cluster; and  
       a computer means for comparing respective said x-y positions of said plurality of focal points of said plurality of light beams for detection of said wavefront.  
     
     
       2. A device as recited in  claim 1  wherein said optical isolating means is an array of lenslets, and said optical focusing means is an individual lenslet in said array of lenslets. 
     
     
       3. A device as recited in  claim 1  wherein said first photodetector and said second photodetector are photodiodes. 
     
     
       4. A device as recited in  claim 1  wherein said first photodetector and said second photodetector are phototransistors. 
     
     
       5. A device as recited in  claim 1  wherein said electronic means converts a plurality of said x-signals from a plurality of said pixels into a representative digital x-signal and said electronic means converts a plurality of said y-signals from a plurality of said pixels into a representative digital y-signal. 
     
     
       6. A device as recited in  claim 1  further comprising a substrate and said plurality of clusters and said electronic means are mounted on said substrate. 
     
     
       7. A device as recited in  claim 1  wherein said first photodetectors of contiguous said pixels are aligned in said y-direction. 
     
     
       8. A device as recited in  claim 1  wherein one said first photodetector of one said pixel alternates in alignment with one said second photodetector of another said pixel in said y-direction. 
     
     
       9. A device as recited in  claim 1  wherein said first electronic circuit is a first wire connected to said first photodetectors in said row for receiving said first electrical currents, and wherein said second electronic circuit is a second wire connected to said second photodetectors in said column for receiving said second electrical currents. 
     
     
       10. A device for detecting a wavefront defined by a plurality of contiguous light beams which comprises: 
       a means for separating a wavefront into a plurality of contiguous light beams;  
       a means for focusing each said light beam of said wavefront to a respective focal point in an x-y plane;  
       a plurality of photocells positioned in said x-y plane, and arranged as a plurality of rows in the x direction and a plurality of columns in the y direction, with each said photocell being responsive to light of a respective said focal point incident thereon to generate an electrical current;  
       a plurality of first electronic circuits for summing said electrical currents in each respective said row of said cluster to generate a respective y-signal for said row;  
       a plurality of second electronic circuits for summing said electrical currents in each respective said column to generate a respective x-signal for said column;  
       a means for receiving said x-signals and said y-signals to determine a respective x-y position for each said respective focal point in said x-y plane; and  
       a means for comparing respective said x-y positions of said plurality of focal points of said plurality of light beams for detection of said wavefront.  
     
     
       11. A device as recited in  claim 10  wherein said plurality of photocells are divided into a plurality of clusters and each said cluster includes a plurality of rows and a plurality of columns with each row having a plurality of pixels aligned in an x-direction and each column having a plurality of pixels aligned in a y-direction, and wherein each said pixel includes a first photocell for generating an x-signal in response to an illumination thereof by said focal point and a second photocell for generating a y-signal in response to an illumination thereof by said focal point. 
     
     
       12. A device as recited in  claim 11  wherein said first photocell and said second photocell are photodiodes. 
     
     
       13. A device as recited in  claim 11  wherein said first photocell and said second photocell are phototransistors. 
     
     
       14. A device as recited in  claim 11  wherein said separating means is an array of lenslets, and said focusing means is an individual lenslet in said array of lenslets. 
     
     
       15. A device as recited in  claim 11  further comprising an electronic means for converting a plurality of said x-signals from a plurality of said pixels into a representative digital x-signal and for converting a plurality of said y-signals from a plurality of said pixels into a representative digital y-signal. 
     
     
       16. A device as recited in  claim 15  further comprising a substrate wherein said plurality of clusters and said electronic means are mounted on said substrate. 
     
     
       17. A method for using a device to detect a wavefront defined by a plurality of contiguous light beams which comprises the steps of: 
       separating a wavefront into a plurality of contiguous light beams;  
       focusing each said light beam of said wavefront to a respective focal point in an x-y plane;  
       positioning a plurality of clusters mounted on said device in said x-y plane, each said cluster including a plurality of rows and a plurality of columns with each row having a plurality of pixels aligned in an x-direction and each column having a plurality of pixels aligned in a y-direction, and wherein each said pixel includes a first photocell for generating a first electrical current in response to an illumination thereof by said focal point and a second photocell for generating a second electrical current in response to an illumination thereof by said focal point;  
       summing said first electrical currents in each said row with a first electronic circuit to generate a y-signal for said row;  
       summing said second electrical currents in each said column with a second electronic circuit to generate an x-signal for said column;  
       receiving said x-signals and said y-signals from said cluster with an electronic means mounted on said device to determine an x-y position for said focal point of said individual light beam incident on said cluster; and  
       using a computer means mounted on said device to compare respective said x-y positions of said plurality of focal points of said plurality of light beams for detection of said wavefront.  
     
     
       18. A method as recited in  claim 17  further comprising the steps of: 
       converting a plurality of said x-signals from a plurality of said pixels into a representative digital x-signal; and  
       converting a plurality of said y-signals from a plurality of said pixels into a representative digital y-signal.  
     
     
       19. A method as recited in  claim 17  wherein said light beams have an ultraviolet wavelength and said method further comprises the step of selecting phototransistors for use as said first photocells and said second photocells. 
     
     
       20. A method as recited in  claim 19  wherein said light beams have an infrared wavelength and said method further comprises the step of selecting photodiodes for use as said first photocells and said second photocells. 
     
     
       21. A method as recited in  claim 17  further comprising the step of aligning said first photocells of contiguous said pixels in said y-direction.